"The ceasefire in Ukraine offers an opportunity, but Russia maintains its ability to destabilize Ukraine and Russia remains in breach of international law," Stoltenberg tells journalists in Brussels, Censor.NET reports citing Alliance News.
"NATO does not seek confrontation with Russia, but we cannot and will not compromise on the principles on which our alliance and the security in Europe and North America rest," he adds.
He also says he sees "no contradiction between a strong NATO and our continued effort to build a constructive relationship with Russia."
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The NATO chief expreessed the Alliance's readiness to assist Ukraine in four areas: cyber security, logistics, advice and assistance to wounded servicemen in the east.